When HN users recommended it
1 HN user recommended this in 2022, in one comment.
20072026
Each tall tick is one HN user's first recommendation. A short tick is the same user again. Click a tick to jump to the comment.
1 HN user recommended this in 2022, in one comment.
Each tall tick is one HN user's first recommendation. A short tick is the same user again. Click a tick to jump to the comment.
Looks like the ones used in the study are an order of magnitude more expensive than the ones on amazon.
Amazon (Plus model), $70: https://www.amazon.com/POWERbreathe-Fitness-Breathing-Traine...
From manufacturer (K3 model), $500: https://www.powerbreathe.com/product/k3/